Automatic sequence cycle controlled advanceable mining prop arrangement



March 25, 1969 HANS-THEODOR GRISEBACH 3,434,39

AUTOMATIC SEQUENCE CYCLE CONTROLLED ADVANCEABLE MINING PROP ARRANGEMENTOriginal Filed Jan. 19, 1966 i Sheet of 2 INVENTOR HANS-THEUUUR smsaamaMarch 25. 1969 HANS-THEODOR GRISEBACH 3,434,389

AUTOMATIC SEQUENCE CYCLE CONTROLLED ADVANCEABLE MINING PROP ARRANGEMENTOriginal Filed Jan. 19, 1966 Sheet of 2 INVENTOR HANS'THEUIJOR GRISEBAEHUnited States Patent Oihce 3,434,389 Patented Mar. 25, 1969 3,434,389AUTOMATIC SEQUENCE CYCLE CONTROLLED ADVANCEABLE MINING PROP ARRANGEMENTHans-Theodor Grisebach, Cappenberg, near Lunen, Germany, assignor toGewerkschaft Eisenhutte, Westfalia, Wethmar, near Lunen, Westphalia,Germany Continuation of application Ser. No. 523,502, Jan. 19, 1966.This application Sept. 29, 1967, Ser. No. 671,896 Claims priority,application Germany, Jan. 21, 1965, G 42,622; Feb. 27, 1965, G 42,952Int. Cl. EZld 15/16, 15/44; Ftllb 31/12 U.S. Cl. 9136 31 Claims ABSTRACTOF THE DISCLOSURE Advanceable mining prop arrangement with hydraulicallyactuata'ble motive means controlled by motive valve means, with eachprop being hydraulically actuatable to change its eflective length foralternate extension into and retraction from supporting engagement withthe mine roof and mine floor upon hydraulic actuation, in combinationwith automatic sequence valve control means operatively connected withthe motive valve means, such sequence valve control means, for example,being separately positioned at a remote distance from the prop unitsufliciently to permit switching of the sequence valve control meanswithout danger to the operator from the resultant changes in conditionof the prop unit and the mine roof area being supported thereby, saidcontrol means so combined with timing means as to operate them in anautomatic timed cycle operation.

This is a streamlined continuation application of copending parentapplication Ser. No. 523,502, filed Jan. 19, 1966, now abandoned.

The present invention relates to an automatic sequence cycle controlledadvanceable mining prop arrangement, and more particularly anadvanceable mining prop arrangeme'nt having a pair of mining propsinterconnected by motive means for alternate actuation to advance thearrangement, in combination with automatic sequence valve control meansoperatively connected with the valve means of the mining proparrangement for regulating the corresponding pressure fluid flowtherethrough in predetermined ordinal sequence and for predeterminedintervals in an automatic cycle operation whereby to advance the miningprop arrangement automatically, preferably from a remote control point.

Mining prop arrangements are known which are usually used in connectionwith a conventional mining conveyor whereby to guide a mining machine,such as a mining planer, along the mine face for the extraction ofmineral therefrom, with the conveyor and in turn the mining machineassociated therewith being advanced in increments or in a more or lesscontinuous manner under the urging force of an advancing cylinder, i.e.,doubleacting piston-cylinder means, or by means of the mining proparrangement associated with the conveyor for supporting the mine roof atthe site of mining operations. Various constructions of the foregoingtype are known in the art as may be appreciated from US. 'Patents2,691,- 514; 2,702,697; 2,745,651; 3,169,377; 3,174,289; 3,186,- 179,and 3,192,722. In particular, a mining prop arrangement is shown in theaforesaid US. Patent 3,192,722,

which includes a pair of prop frames, each including a pair ofextensible and retractable mining props interconnected at their headsand feet by a roof cap and base respectively, with such frames beingoperatively interconnected by a piston-cylinder means, such that uponenergizing the piston-cylinder means in a first step, the prop frameconnected to one of the moving parts is advanced whereupon energizing inthe second step results in the advance of the other frame connected tothe other part. Of course, when a particular prop frame is to beadvanced, the same is retracted from engagement with the mine roof.

Mining prop arrangements of the foregoing types have been provided inmany embodiments, but in the usual instance the prop units, composed ofa pair of prop frames operatively interconnected by a piston-cylindermeans, are actuated via manually operated valves. These are generallycombined in a control block in such a manner that the retracting of theprops of the particular prop frame to be advanced, the advancing of suchprop frame by energizing the piston-cylinder means and the extension ofthe advanced prop frame to place the roof cap thereof in supportingengagement once more with the mine roof, must be carried outindividually by hand.

Despite the usual manual control for the advancing of a prop unitcomposed of a pair of prop frames interconnected by piston-cylindermeans, hydraulic, pneumatic and electrical transmission means have beenutilized nevertheless for attaining the same type of actuation of theprop unit parts from a central point in the case where large groups ofprop units are intended to be operated simultaneously or for that matterall of the prop units in a particular mine area being Worked. To attainsuch central control, however, understandably, long cables ortransmission lines must be utilized to reach the multiple number of propunits in question, and this results in great expense not only for thecables and/or lines and the complicated control equipment required butalso in terms of damage to the cables and/or lines as well as to thecomplicated equipment, considering the comparatively rigorous treatmentto which such elements are subjected un der normal mining operations.

It has also been proposed to employ so-called manipulators, i.e.,portable remote control central units, which remotely control a givengroupof mining prop units.

In all constructions and arrangements used heretofore, however, anycontrol, especially remote control of the advanceable mining proparrangement and concomitantly of the positioning of the mining machineand/or the conveyor, etc, has been undertaken by equipment which couldonly control the individual steps or functions in a given prop unit,rather than automatically in a timed cycle, all of such steps orfunctions following one another without further control. For thispurpose, wireless transmitters and the like have been used at a remotepoint for controlling, via a receiver, control means installed in amining machine or other equipment utilized in the mining operations toaccomplish the particular actuation desired.

Particularly, the transmitter is adjusted at a different frequency orpulse to control a given advancement individual function or step, suchas in a mining prop unit. Such mining prop unit concomitantly would havereceiver means associated therewith receptive to the differentfrequencies or pulses of the transmitter whereby to control anindividual function or step in the operation of the mining prop unit independence upon the selected frequency. Understandably, the fruition ofthe foregoing involves relatively complicated transmitters and receiversand even the results are not completely effective.

In this connection, it must be realized that in order to advance a givenmining prop unit, such as one of the type shown in U.S. Patent3,192,722, mentioned above, firstly one prop frame must be retractedfrom engagement with the mine roof, while the other prop frame remainsengaged therewith, secondly the one movable part of the piston-cylindermeans which is connected to such one prop frame is then advanced in thedesired direction to advance in turn the one prop frame, thirdly suchone prop frame is extended once more into engagement with the mine roof,fourthly the other prop frame is retracted from engagement 'with themine roof, fifthly the moving part of the piston-cylinder meansconnected to such prop frame is energized to advance such part in thedesired direction and in turn to advance such other prop frame, andsixthly such other prop frame is extended once more into engagement withthe mine roof. Each of such six steps has been controlled heretofore bya separate frequency where a remote control transmitting equipment hasbeen used in connection with a corresponding receiving equipment, thereceiving equipment being located near or on the individual prop unit.Any such proposals heretofore suggested for the automatic control of themining equipment at the mine face, such as the advanceable prop units,etc., have contemplated automatic control in the sense that completelyautomatic control was utilized with concomitant disregard for the normalvariations to be encountered in mining operations. Specifically, themine face conditions, the skill of the personnel, as well as thetechnical conditions of the mine roof and of the advanceable prop frameunit itself, are such that under the present conditions of developmentcompletely automatic control for extracting mineral from the mine faceis far from advisable or attainable. At present, it is still necessaryfor the operating personnel to pass along from mining prop frame unit tomining prop frame unit in order to carry out the immediate supervisionof the automatic operations being undertaken, despite the fact that suchoperations are intended to be automatic. This is to permit minor, yetimportant, adjustments to be made in the disposition of the mining propunits, the conveyor associated therewith, etc. For the most part,completely automatic mining equipment, and especially advanceable miningprop units, utilizing various remote controls, are still too costly forwidespread use, and the sensitivity of the equipment renders theapplication thereof extremely limited considering the normally adverseand rigorous conditions met in mining operations.

In the case of the usual individual manual control, the operator must ineach instance remain at the mining frame unit until the complete advanceof the unit has been completed. However, it is just during thisadvancing operation of the unit that a special zone of danger is presentin the region of the unit being advanced, since during such advance theroof thereabove frequently caves in. This is understandable since in theadvance, a portion of the roof is robbed of support to permit aparticular mining prop frame to be displaced by the piston-cylindermeans. It has thus been proposed to arrange the control block carryingthe switches for the valves to energize the unit for the desiredpurposes, not on the particular frame or unit whose advance is to becontrolled thereby but on the neighboring frame or unit. This willpermit the operator to withdraw from the direct zone of danger duringthe advancing steps.

It is an object of the present invention to overcome the foregoingdrawbacks and to provide an automatic sequence cycle controlledadvanceable mining prop arrangement.

It is another object of the present invention to provide an advanceablemining prop arrangement having a pair of mining props interconnected bymotive means for alternate actuation to advance the arrangement, incombination with automatic sequence valve control means operativelyconnected with the valve means of the mining prop arrangement forregulating the corresponding pressure fluid flow therethrough inpredetermined ordinal sequence and for predetermined intervals in anautomatic cycle operation whereby to advance the mining prop arrangementautomatically, preferably from a remote control point.

It is still another object of the present invention to utilize automaticcontrol means which permit the retraction advancement, and extension ofone prop frame of the prop unit followed by the retraction, advancementand extension of the other prop frame of the prop unit in an automaticmanner, with the steps being in ordinal sequence and with the controlbeing for predetermined periods of time, so that the over-alladvancement will be accelerated as compared with the time requiredheretofore for manual advancement of a prop unit, or previously utilizedremote control advancement.

It is still another object of the present invention to provide controlmeans of the foregoing type for a plurality of mining prop frame unitsdisposed along the mine face for the simultaneous and/or successiveadvancement of such units to reduce the time interruption betweensuccessive passes of the mining machine along the mine face in order toaccomplish more economically and more efficiently the extraction ofmineral.

It is still another object of the present invention to carry out theautomatic advancement of one or more mining prop frame units in such amanner there is no longer any danger to the operator of the controlequipment as heretofore occurred, and in such a manner that the operatoris accorded greater mobility of movement at the mine site whereby toattend to other duties once a. particular control for the automaticadvancement of a prop unit has been initiated.

It is a further object of the present invention to provide a combinationof control elements together with an advanceable mining prop frame unitin a durable and inexpensive manner, the arrangement contemplatingsimple and inexpensive elements of construction, and readily replaceableparts.

Other and further objects of the present invention will become apparentfrom a study of the within specification and accompanying drawings, inwhich:

FIG. 1 is an enlarged schematic top view of an automatic sequence valvecontrol means utilized for controlling a prop frame unit in accordancewith the present invention; r

FIG. 2 is a schematic top view of a plurality of individual prop frameunits disposed in side by side relation with each having an automaticsequence valve control means in accordance with the present inventionassigned thereto, such sequence valve control means being operativelyinterconnected for controlling the advancement of the particular unitsin a given predetermined sequence;

FIG. 3 is a schematic view of an alternate manner of controlling theswitch means for initiating the operation of the automatic sequencevalve control means of the invention;

FIG. 4 is a schematic side view of a prop frame of an advanceable miningprop frame unit in accordance with the present invention having wirelessreceiving means thereon for controlling the advancement of the unit; and

FIG. 5 is an enlarged schematic perspective view of a particularembodiment of the automatic sequence valve control means of the presentinvention which is controlled remotely by a wireless transmittingdevice.

It has now been found in accordance with the present invention that anadvanceable mining prop arrangement which comprises an advanceable propunit including hydraulically actuata'ble motive means having a firstmotive part and a second motive part operatively interconnected for backand forth alternate longitudinal displacement with respect to each otherupon corresponding alternate hydraulic actuation, motive valve meanscontrolling such alternate hydraulic actuation, prop means including afirst prop connected to said first motive part for longitudinaldisplacement therewith and a second prop connected to said second motivepart for longitudinal displacement therewith, each said prop beinghydraulically actuatable independently of the other to change theeffective length thereof for alternate extension into and retractionfrom supporting engagement with the mine roof and mine floor uponcorresponding alternate hydraulic actuation, and first prop valve meansfor said first prop and second prop valve means for said second propcorrespondingly controlling such alternate hydraulic actuation, incombination with automatic sequence valve control means operativelyconnected with said motive valve means, first prop valve means andsecond prop valve means to actuate said valve means for regulating thecorresponding hydraulic flow therethrough in predetermined ordinalsequence and for predetermined intervals in an automatic cycleoperation, said sequence valve control means being switchable from aninactive condition to an active condition wherein, when both said propsare extended into engagement with the mine roof, said sequence valvecontrol means in sequence automatically firstly actuates said first propvalve means for retraction of said first prop from engagement with themine roof, secondly actuates said motive valve means for longitudinaldisplacement of said first motive part and said first prop with respectto said second motive part and said second prop in a given longitudinaldirection of advance, thirdly actuates said first prop valve means forextension of said first prop into engagement with the mine roof,fourthly actuates said second prop valve means for retraction of saidsecond prop from engagement with the mine roof, fifthly actuates saidmotive valve means for longitudinal displacement of said second motivepart and said second prop with respect to said first motive part andsaid first prop in said direction of advance, and sixthly actuates saidsecond prop valve means for extension of said second prop intoengagement with the mine roof, may be advantageously provided.

Preferably, supplemental manual switch means are provided in operativeassociation, separately from said sequence valve control means, withsaid motive valve means, first prop valve means and second prop valvemeans to permit alternative manual actuation of said valve means. Also,it is expedient to provide the sequence valve control means at a remotedistance from the prop unit in question to permit control without dangerto the operator from resultant changes in condition of the prop unit andthe mine roof area being supported thereby.

In particular, the sequence valve control means include an automatictimer device which when switched from inactive to active conditionpasses through a timed cycle to control the actuation in turn of saidvalve means in the required sequence, preferably with the timer devicepassing through a pre-active condition of pre-set duration prior toattaining the active condition, as a safety delay period to permit theoperator to leave the immediate prop unit site before the resultantchanges in condition of such prop unit and the mine roof area beingsupported thereby occur upon the timer device attaining the activecondition.

Such timer device may include a control block having a dial face withvalve means switch contacts to control the corresponding hydraulic flowthrough the various valve means and a sweep-hand switch contact movablefrom a starting position, preferably initially through a pre-activeportion of the dial for attaining the pre-active condition of pre-setduration and thence, through the active portion of the dial in contactfor predetermined intervals in time controlled sequence ordinally withthe valve contacts to achieve the automatic advancement of the prop unitin question.

Furthermore, the automatic timer device may include a drive linkageoperatively connected with displaceable cam means and cam actuatableresponse means operatively connectable with the valve means to controlthe correspondingly hydraulic flow therethrough, with the drive linkagebeing energizable to displace the cam means to actuate follower meansforming a part of the response means to thereby control the valve means.

The automatic timer device, whether utilizing a control block dial andsweep-hand switch contact or a drive linkage cam means, cam actuatableresponse means, etc., may be operated by a clock mechanism, such as aspring driven or electrically driven clock mechanism, or an electricalmotor, or similar connection means, so as to attain upon switching frominactive to active condition a predetermined duration automatic cyclefor ordinal sequence switching of the various valve means to attain theadvancement of the prop unit in question.

Understandably, a plurality of advanceable prop units of the instanttype, each in combination with a respective automatic timer device, maybe provided in succession in operative adjacency for the simultaneousand/or successive operation of the timer devices via cable means for thesuccessive and/or simultaneous advancement of the various prop units inthe group.

Of course, remote control means may be provided in connection with theautomatic timer device of the present invention to switch the same onand off whereby to attain the inactive and active conditions thereof,such remote control means contemplating in particular a pulse signaltransmitting wireless device remote from the mining prop arrangement anda pulse signal receiving wireless device operatively connected with theappropriate timer device to actuate the same upon the pulses received.The energy for carrying out the foregoing may be provided by bat teriesassociated with the particular prop frame unit or by spring energy, suchas a coil spring in wind-up clock- Works, or the like.

As will be realized as well, where utilized herein, i.e., both in thespecification and claims, the term hydraulic is meant to cover pressurefluid or pressure fluid operated equipment whether per se hydraulic orpneumatic, or the like.

Referring to the drawings, FIG. 1 shows an automatic timer device inaccordance with one embodiment of the present invention including acontrol block 1 having an adjustable short-time clockwork 2 therein withan adjustment disc or dial face 3 on the upper side thereof along whichsweep hand 4 carried by spindle 5 travels such that the sweep handswitch contact 6 traces a circular path about spindle 5 as axis alongthe dial face 3. The free end 7 of sweep hand 4 is provided with anoblique surface 8. Adjacent one portion of the dial face 3, a releasablelocking member 9 is provided which contains the long arm 10 and theshort arm 11, locking member 9 being pivotable about pivot 12 on controlblock 1. A Bowden cable or the like is provided adjacent locking member9, including the flexible tube 13 and the flexible cable 15 disposedtherewithin for axial displacement therewithin, cable 15 having apushpin 14 adjacent the short arm 11 of locking member 9, whereby uponprojection of pushpin 14 outwardly through the corresponding end of tube13 locking member 9 will be released to permit sweep hand 4 to initiateits movement in the direction of arrow 16. Upon completion of the sweephand movement around dial face 3, the same reaches the end position stop17.

In accordance with a preferred embodiment of the present invention, asimilar Bowden cable is provided at the end position stop 17 on controlblock 1 including the flexible tube 13 and the flexible cable 15'axially displaceable therewithin and having at the outer end thereof apushpin 18. Thus, when the sweep hand 4 reaches end position stop 17oblique surface 8 will strike pushpin 18 forcing the corresponding cable15 inwardly within tube 13. In this connection, the other end of thecable 15 is arranged at a successive control block of the type inquestion with an appropriate pushpin for controlling the releasablelocking member thereat similar to the locking member 9 adjacent thepushpin 14 shown in FIG. 1. Hence, a plurality of timer devices inaccordance with the present invention may be started successively afterthe sweep hand of the prior control block of a previous timer device hasreached its end position stop. This is seen more clearly from FIG. 2.

In connection with a particular feature of the embodiment shown in FIG.1, the spindle may be connected with a clockwork, either electricallyenergized or energized by a loaded spring, such as a coil springconventionally used for wind-up clocks. In the latter instance, thesweep hand 4 may be turned manually in the direction of arrow 19 toplace the same behind the long arm of the locking means 9 until lockingmeans 9 is released for the next actuation desired. Of course, ifspindle 5 is operated electrically, then stop 17 may be releasablyarranged to permit the sweep hand 4 to pass by the same to the initialstarting position, wherupon by suitable energizing of the electric motoror similar means used for driving the same, the sweep hand may be usedagain for the complete sweep of the entire face. Locking member 9 may beappropriately modified or omitted in the case where electrical motormeans are used to rotate spindle 5, and/ or sweep hand 4 may be attachedto spindle 5 in a sliding friction manner to permit the simpleadjustment of the sweep hand with respect to spindle 5 in the same wayas the hands of a clock may be rotated on the spindle while the spindleis held from rotation.

In the usual case, upon release of locking means 9 to start the sweep ofsweep hand 4 along dial face 3, the sweep hand passes through apreactive portion 20 of the entire face to achieve a preactive conditionof the timer device, i.e., a delay period which will permit the operatorto remove himself from the immediate vicinity of the mining prop unitbefore the advance to ensure his safety. The preactive period may beadjusted in a given manner by adjusting the inactive portion of sweephand 4 closer or farther from stop 17, utilizing indicia provided ondial face 3 for measuring the time delay desired. As will be understoodby the artisan, the locking member 9 may be arranged such that the samemay be positioned at various places closer to or farther from stop 17 orcontrol block 1 to achieve a corresponding variation in the time delaypermitted during the preactive condition of the sweep hand 4. Once sweephand 4 has moved from inactive through preactive condition, the samearrives at the active portion 21 of dial face 3 containing the six valveswitch contacts 22, 23, 24, 25, 26 and 27, which are ordinarilypositioned on the dial face and operatively connected by means not shownwith the motive valve means, first prop valve means and second propvalve means of a particular prop unit to achieve upon individual contactwith switch contact 6 of sweep hand 4 the actuation of the appropriatevalve for a predetermined interval in a time controlled ordinalsequence. While the actual valve means are not shown, as the artisanwill appreciate, these elements are conventional and the timer deviceincluding control block 1 merely acts as an automatic time controlselective mechanism to complete the cycle of actuation by any means suchas servomotors or the like, relating to the retraction of the first propframe, advancement thereof, extension of such first prop frame,retraction of the second prop frame, and advancement thereof, followedby extension of such second prop frame to attain the original fullysupported condition of the prop unit.

As may be seen more clearly in FIG. 2, the combination of the timerdevice of the present invention in the form of a control block In withan advanceable mining prop unit 39a is shown, the prop unit comprisinggenerally one prop connected with one part of the motive means with theother part of the motive means being connected with another prop, sothat upon retracting the one prop and advancing the same by the motivemeans connected therewith, such one prop may be extended once more forthe engagement with the mine roof and the other prop can be retracted,then advanced with the motive part to which the same is connected,followed by extension of such prop once more. Specifically, the frameunit 39a includes frames 29a and 37a interconnected via the motive means33a with control block 1a having the adjustable short-time clock-work orsimilar mechanism 2a situated therein for achieving the time sequenceautomatic control of the valve means in question as discussed more fullyin connection with the operation of the control block of FIG. 1. Frame29a contains base 28, preferably of resilient material so that the samemay accommodate unevenness in the mine floor, as well as a pair ofupright props 30 attached to base 28, and preferably with a roof cap(not shown) interconnecting their upper ends in the conventional manner.The motive means 33a contains the double-acting piston (not shown)carried by the piston rod 32 and the double-acting cylinder 34 throughthe ends of which the corresponding ends of the piston rod 32 extend.The ends of piston rod 32 are connected by straps 31 with base 28 whilecylinder 34 is connected by straps 35 with base 36 of frame 37a. Frame37a contains props 38 extending upwardly from base 36, preferablyprovided with a roof cap (not shown) in the same manner as props 30.

Accordingly, frames 29a and 37a are similar in construction, with theprops 3t and 38 being of the usual type, utilizing the hydraulic jackprinciple to extend and retract such props for engaging and retractingthe same from engagement with the mine roof thereabove, i.e., eitherdirectly or through the intermediary of an appropriate roof cap disposedthereat. Preferably, not only the bases 28 and 36, but also the straps31 and 35, are made of resilient material to permit the same to bedeformed somewhat in order to allow the individual prop frames and thecomposite prop unit 39a to accommodate unevenness in the mine floor andthe mine ceiling.

Considering the use of a control block of the type shown in FIG. 1, uponpassage of sweep hand 4 to the first switch position contact 22, thecontrol valve for the hydraulic actuation of props 30 is actuated (byconventional means not shown) to retract props 30 from engagement withthe mine roof. When sweep hand 4 reaches second switch position contact23, the control valve for actuating the motive means 33a is energized toadvance in the longitudinal direction toward the right, as viewed inFIG. 2, the piston and accompanying piston rod 32 whereupon prop frame29a, now released from engagement with the mine roof, will be advancedtherewith with respect to the position of frame 37a. When sweep hand 4reaches third switch position contact 24, the control valve for props 30will cause the extension of such props once more into engagement withthe mine roof. When sweep hand 4 reaches fourth switch position contact25, the control valve (not shown but of conventional type) for actuatingprops 38 will be energized to cause retraction of props 38 fromengagement with the mine roof. When sweep hand 4 reaches fifth switchposition contact 26, the opposite portion of the motive means 33a willbe energized so as to force cylinder 34 in the same forward direction tothe right, as viewed in the drawing, thus advancing as well prop frame37a with respect to prop frame 29a. When sweep hand 4 reaches sixthswitch position contact 27, the control valve for props 38 will oncemore extend such props into engagement with the mine roof.

Thus, by a simple timer device, an automatic cycle may be used toaccomplish the six above-mentioned steps for advancing a prop unitcomposed of a pair of prop frames interconnected by a motive means, suchas a double-acting piston cylinder arrangement. The construction of suchan arrangement is conventional as may be appreciated, for instance, froma study of the aforementioned US. Patents 3,192,722, 3,174,289, and3,186,179.

The timer device of the present invention, as aforesaid, may be a springoperated clockwork or an electrically operated motor, or the like. Inaccordance with a preferred feature of the present invention, more thanone prop frame unit may be advanced automatically successively orsimultaneously, whereby to reduce the total time of setting up thearrangement for a particular further sweep of the mining machine inquestion along the mine face being worked. Thus, as seen in FIG. 2, themining prop units 3912, 39c, 39d, and 39e are provided as a group withunit 39a, each having an appropriate timer device in the form of acontrol block 1b, 1c, 1d, and 1e respectively, as well as an appropriatemotive means in the form of a double-acting piston cylinder arrangementinterconnecting the adjacent prop frames, for instance as shown bymotive means 33!) and prop frames 29b and 37b of prop frame unit 39b.The appropriate adjustable short-time clockworks 2a, 2b, 2c, 2d, and 2eof the corresponding control blocks are operatively interconnected inthe embodiments shown in FIG. 2 for successive actuation of the propunits, one after the other, utilizing the preferred arrangement ofBowden cable connections discussed with regard to FIG. 1 above. Thus,the Bowden cables 13a, 13b, 13c, and 13d operatively interconnect thecorresponding clockworks so that upon the particular sweep hand 4 of aprevious clockwork reaching the end position stop, the oblique surfaceof such sweep hand will push via the appropriate pushpin the flexiblecable adjacent thereto inwardly to cause the other end of such cable torelease the locking means of the next successive clockwork on the nextsuccessive prop frame unit. The particular details may be appreciatedmore fully from a study of FIG. 1 wherein the tube 13 is connected witha previous control block in the succession while the tube 13' isconnected with a subsequent control block in the succession.

An alternate embodiment of the present invention in FIG. 3 contemplatesa successive or even simultaneous control of the switching means for thevarious timer devices of successively adjacent prop frame units (notshown) of a group meant to be controlled. The cable 94 is appropriatelymounted for longitudinal displacement and carries thereon a thickenedportion or lu-g 95 which is meant to coact with an appropriate arm 97 or98 of a control lever 96 used to actuate directly or indirectly thetimer device of a particular prop frame unit. Schematically consideringthe prop frame units 39a through 39:! inclusive, as containing controllevers 96a-96d inclusive, respectively, the advancement of the propunits may be attained successively upon the longitudinal displacement ina downward direction, of cable 94, as viewed in the drawing, so that thelug 95 successively actuates control levers 96a-96d via the appropriatearms 98a- 98d inclusive, or in the opposite direction via arms 97a- 97dinclusive. This alternate embodiment may include a plurality of separatecables 94 arranged to control a plurality of successive prop frameunits, so that the first unit in each separate series may be actuatedsimultaneously, then the next, and so on, until the last prop frame unitin each group is actuated. Moreover, by utilizing a plurality of lugs 95on the same cable 94 at spaced apart distances therealong, simultaneousas well as successive actuation of various prop frame units may beattained. Specifically, the first, eleventh, twenty-first, thirty-first,etc., prop frame units in the series may be actuated simultaneously byan appropriate switching means of the type shown in FIG. 3 upondisplacement of cable 94 to bring the adjacent lug 95 into controllingcontact with the control levers of the first, eleventh, twenty-first,thirty-first, etc., prop frame units. After such prop frame units havebeen simultaneously advanced, then the second, twelfth,

twenty-second, thirty-second, etc., prop frame units may be advanced,and so on, in succession, until the last set of prop frame units hasbeen actuated. Suitable means, conventional in the art, may be used toprevent the further displacement of cable 94 and lu-g 95 until thecompletion of the advancement cycle of a previous prop frame unit, i.e.,before the next prop frame unit in succession is to be actuated andadvanced. Better control over the operation is attained thereby and inthe event of an unsuccessful advance, the reasons for the mishap may beascertained more readily.

In connection with a further embodiment of the present invention, asshown in FIGS. 4 and 5, a prop frame is provided which includes theupright props 41 and 42 interconnected by the resilient base strap 44and the roof cap 43. Frame 40 is similar in construction to theindividual prop frames shown in FIG. 2 and the props utilize thehydraulic jack principle to change their effective length whereby toextend such props and in turn the roof cap into engagement with the mineroof and retract such props and in turn the roof cap from engagementwith the mine roof. Understandably, an appropriate second frame (notshown) is used with frame 40, such frames being interconnected by asuitable motive means, such as a piston cylinder arrangement of the typeutilized in the construction of FIG. 2, whereby the resulting prop frameunit may be advanced in the desired way. Associated with frame 40 is acontrol block 45 which may be manually operated by the handle 49 andwhich may be operated automatically in accordance with the presentinvention, in this case by remote control. For this purpose controlblock 45 is operatively connected with a servomotor of the conventionaltype within servo-motor housing 46, the control block and timer devicebeing controlled by the pulse signal receiving wireless device ortransistor receiver 47 having the antenna 48, such receiver 47 operatingin dependence upon signals received from a pulse signal transmittingwireless device 50 remote from the prop frame unit as seen in FIG. 5.Transmitting device 50 contains an actuating button 51 to send thesignal via the antenna 53, with appropriate dials 52 being provided toselect a predetermined frequency for governing a particular receiver 47tuned to such particular frequency. The construction of the wirelesstransmitter 50 and receiver 47 is conventional and is therefore notshown in great detail since these elements are used as old elements in anew combination with a mining prop unit arrangement for the automaticadvancement thereof in a time cycle. Upon receiving a signal from thetrans mitting device 50, receiver 47 energizes an electromagnet 54.Thus, the armature 55 pivoted about point 56 is displaced to cause inturn the balance wheel brake 57 to disengage the adjacent balance wheel,so that fork 58 at the free end of such balance whee-l can urge againstteeth 59 of the timing mechanism wheel 60 disposed on the shaft 61 tocause rotation of such shaft. Shaft 61 contains a small gear wheel 62which operatively engages the large gear wheel 63 on shaft 64. Thiscauses the rotation of roller 65 disposed on shaft 64 such thatprojections 66, 67, 68 and 69, or other cam means, will engageoperatively the rocker levers 70, 71, 72 and 73, respectively, mountedon rod 74, or other follower means, whereby to cause the pistons 75, 76,77, and 78, respectively, to be displaced within low pressure valves 79,80, 81 and 82 operatively connected via flow lines 83, 84, 85 and 86with the servo-motor (not shown) within housing 46. In response topressure actuation via a given flow line, the servo-motor in turn causescorresponding movement of member 87 which appropriately controls theflow of pressure fluid, entering control block 45 through conduit 88,into the appropriate branch 'lines 90, 91, 92 and 93 for effecting propunit advancement. The movement of member 87 also governs the returnflow, respectively, from lines 90, 91, 92 and 93 through control block45 and out via conduit 89. Conduits 88 and 89 may be connected in theconventional way with a pressure fluid reservoir. The pressure fluid inthis instance as well as that contemplated in the operation of the unitsshown in FIG. 2 may be hydraulic or pneumatic, both such systems beingcontemplated by the terminology used in the instant specification andaccompanying claims.

The transmitter 50 may be portable in nature, and thus carried by theparticular operator at a safe distance from the prop frame unit beingcontrolled to advance the same. Transmitter 50 will thus be batterypowered and may be cheap, light, and simple in construction. The same istrue for receiver 47, since its purpose is only to energize a smallelectromagnet 54 upon receiving a signal from transmitter 50. Theelectromagnetic force is extremely small since this merely controlsbrake 57 for the timing mechanism, run by a spring such as a clockworkspring (not shown), operatively connected to shaft 64, whereby to rotateroller 65 and in turn cause actuation of the valve means. Alternately,if an electric motor (not shown) is used to rotate shaft 64, a switch(not shown) similar in operation to brake 57 may be used for controllingsuch motor, the motor being ener gized by the same different battery orother power source used for receiver 47 and/ or electromagnet 54.

Projections 66 to 69 are positioned to attain a predetermined sequenceof valve control for predetermined intervals, appropriately with thecomplete cycle of advancement of the particular prop unit correspondingwith a complete rotation (360) of roller 65. Roller 65 may contain apreactive portion to achieve a preactive condition after brake S7 isreleased and prior to engagement of the first projection with theappropriate rocker lever to initiate the cycle of ordinal sequence ofsteps for advancing a given prop frame unit. Thus, if perchance aworkman is too near the particular prop frame unit being advanced, therewill still be time for such workman to remove himself without danger.

An audible or visual signal may even be provided near the particularprop frame unit being advanced, not only in connection with theembodiment of FIGS. 4 and S but also that of FIGS. 1, 2 and/ or 3, sothat during any preactive interval, any workman nearby can be alerted tothe automatic cycle which has been initiated to prevent mishap.

Thus, in accordance with the present invention, the timer deviceincluding a control block may be switched from inactive to activeposition automatically from a remote point or manually by a workman atthe immediate site of the unit being advanced, with an appropriate timedelay or preactive period during which such operator can remove himself,such that the advancement may take place automatically and in propersequence. Thus the individual steps or movements of the props withrespect to the mine roof and with respect to one another may take placein a cycle allocating a predetermined, yet adjustable, period of timefor the completion of such individual movement or step, to attain a moreefiicient advance of prop frame units than has been possible withprevious constructions, whether completely automatic, remote or manualin nature.

The operator is left with sufiicient time to devote to other duties,since upon actuating the switch lever at the control block for aparticular prop frame unit, the automatic cycle for accomplishing theprop frame unit advance takes place, whereupon the operator can get setfor the actuation of the next timer device. Furthermore, due to thepreferred preactive delay period, the operator may remove himself fromthe immediate site of the prop frame unit, and preferably the timerdevice and control block for one particular prop frame unit may besituated on the next adjacent prop frame unit, so that upon initiationof the automatic cycle of advancement, the operator is already removedfrom the danger area. In no case is it necessary for the operator toremain in the immediate vicinity of the advancing prop frame unit, as

in the past, for attending to the individual control steps to retractthe first frame, advance such frame, extend such frame, retract thesecond frame, advance such second frame and extend such second frame.Instead, due to the automatic performance of the control procedure inaccordance with the combination of the present invention, the operatormay turn his attention to the next prop unit to be advanced or othermatters.

Advantageously, it is advisable to provide along side the control blockand/or timer device of the present invention whether remotely operatedby Wireless means or not, a manually actuated control device of theconventional type. This will permit not only emergency manual actuationof a particular prop frame unit but also an attentive manually activatedcorrection control. In the latter instance, in the event of mishap, orin the event that one step in the cycle is not completed for some reasonbefore the next step in the time cycle must take place, upon inspection,the operator may correct the situation by manually actuating the valvemeans to accomplish the incomplete advance or even to change thelongitudinal position of the prop frame unit or to adjust the positionthereof to attain a more secure support of the mine roof, i. e.,depending upon the particular conditions met. Since a manual correctioncontrol is possible, the timer device of the present invention can beconstructed more simply and more cheaply than otherwise. The timerdevice understandably need only be capable of performing properly duringthe normal automatic control cycle but not for more precise correctioncontrol which is necessary in practice as where there is an irregulardevelopment of the miner-a1, such as coal or rock, which requires morespecific attention than is inherently impossible to achieve withautomatic cycle advancement.

While it is known to control an advanceable prop support unit of theinstant type from a central point, as for instance from the dischargeend of the conveyor, remote from the actual mine extraction site, thisnecessarily presupposes the provision for a large number of controllines which are constantly endangered by the vigorous operationsindigenous to mining. Completely safe arrangements for the control linesare not possible to attain. Moreover, since the prop frame units are ata great distance from the control point, they cannot be checked toassure that they are operating properly unless a surveillance device isprovided to indicate the proper completion of a previous controlledadvancing step, whether retraction or extension of a particular propframe or advancement of a particular prop frame. Indeed, the use ofsurveillance devices of such type is extremely costly and burdens theeconomy of the over-all operation.

-In accordance with the present invention, the central control from aremote distance is attained not by the use of control lines which may bedamaged during the mining operations, but rather by wirelesstransmitting and receiving equipment. As will be appreciated by theartisan, such wireless equipment is effective whether the distance ofthe transmitting equipment is near or far from the receiving equipment.Indeed, relatively short distances within the mineway, such as two orthree hundred meters in length, are easy and inexpensive to accommodatewith existing transmitting devices since the transmitter need only bevery small to govern the operation at such a distance. A portabletransmitter may include its own current in the form of a battery and beconveniently carried by the operator, even where it is encapsulated forprotection from fire-damp. The operator thus may control a conventionalframe unit from the direct vicinity thereof or else from a greatdistance away in order to bring about the advancement of the unit, andalso a number of frame units in a group may be similarly actuated foradvancement simultaneously or successively. Where a remote controlwireless transmitter and receiver are used, various receivers onselected frame units may 'be assigned different frequencies while othersare assigned the same frequencies, so that simultaneous and/orsuccessive actuation of the timer devices of such units may be attainedin any given ordinal sequence in dependence upon the frequency selectedfor the transmitter and the receiving frequency of a particularreceiver.

In connection with the embodiments of FIGS. 1 and 2, on the one hand andFIGS. 4 and 5 on the other hand, and even in connection with that ofFIG. 3, the control block which may be utilized with the timer devicemay contain a servo-motor, controlled by the time switch and utilizedfor imparting power pulses to control the valve means and in turn thehydraulic pressure fluid flow necessary for the individual movements orsteps to attain a complete cycle of advancement. Where a wirelesstransmitter and receiver are employed rather than other switch ing meansfor attaining the active condition of the timer device, such as bymanual control, the servo-motor and time switch or control blockmechanism may be utilized as the important units for controlling thevalve means and such elements may be individually replaceable forversatility in operation with a minimum of interruptions. The timerdevice need only be small and primitive in construction provided thesame is sufliciently dependable in operation, considering that the sameneed not itself directly actuate the control members or control valvesfor controlling the flow of hydraulic or pneumatic pressure fluid, sincethis may be accomplished by servo-motors of the conventional type andthe like.

Preferably a given control block, timer device containing a servo-motorand the like should be assigned to each prop frame unit or to aplurality of prop frame units to be actuated simultaneously as a group.Also, as aforesaid, each unit should be provided with its own manualswitching control to accomplish minor adjustments or corrections in thepositioning of the particular prop frame unit.

Utilizing the arrangements in FIG. 2 and 3, regardless of whether theinitiation of the timer device is attained manually or by remote controltransmitting and receiving wireless means, sequential on simultaneousactuation of a plurality of prop frame units is attainable whereby theadvancement of the entire array of mine face prop frame units can beaccomplished within a period of time which is approximately equal to oronly insignificantly longer than the time heretofore necessary foradvancing a markedly smaller number of prop frame units. Theconventional advancement by manual switching of a prop frame unit maytake about 1 /2 minutes and in comparison utilizing the simultaneousoperative interconnection of a number of timer devices in accordancewith the present invention, ten successive groups of prop frame unitsmay be advanced which may make up the units disposed along the entirelength of the mine face. Thus, if ten units make up a given group, onehundred units may be advanced in only minutes in accordance with theautomatic cycle advancement of the present invention, whereas 150minutes would be normally required for individual manual actuation ofsuch units.

Various arrangements for achieving the foregoing may occur to theartisan, such as by the connection of the control means, using cablemeans of the type contemplated in FIGS. 2 and 3 herein for instance,first to actuate a given prop frame unit, next to actuate the unit onone or the other side adjacent thereto or both units adjacent thereto,and so on. Suitably, one or several prop frame units may even be omittedfrom automatic control or selectively passed over as for example, whereit is advisable to retain an original support of the mine roof in theimmediate vicinity of a fault or at the end of the mine face area beingworked.

In the case where a clockwork is used in the timer device of theinvention, the same may be automatically returned to its startingposition by rewinding a coil spring which may energize the same, orotherwise, this being accomplished at the end of the cycle, not onlyautomatically but manually, by suitable means which will occur to theartisan. A brake or other releasable locking means is preferablyassociated with the timer device of the invention which may be releasedmanually, via an electromagnet in response to a pulse or signal emittedfrom the transmitter as in FIGS. 4 and 5, or released by mechanicallinkage means as in the case of the embodiment of FIGS. 1 and 2.

Understandably the nature and construction of the timer device of thepresent invention may take any form whatsoever although a convenientform is a spring operated short-time clockwork, possibly one having anidle initial movement or preactive condition before the active conditionduring which the cyclic automatic control in sequence of the valve meansoccurs to accomplish the advancement of a given prop frame uint orunits.

A further embodiment of the time switch which may be utilized herein isa conventional laminated switch impeded, under constant dependence upontime, by the force of adherence of a flowing mass, in particular, aviscous mass such as dimethylpolysiloxane. The switch is provided with amanually actuated switch lever arranged concentrically in the particularcontrol block and which is placed under the action of a spring force andalso connected via a free wheel with a brake for the timer device insuch a manner that the lever or a pin thereon under impedence of theflowing mass controls the valve means for achieving the advancement ofthe unit. A corresponding transmission means connected with such levermay achieve such control or a servo-control in the form of a servo-motormay be used which in turn controls operatively the valves to permithydraulic fluid flow to and from the operative cylinders to achieve theretraction and extension of the prop and the longitudinal displacementof the motive means parts, such as a piston and a cylinder, with respectto one another. Because of the rotation of the switch lever, which isactually mounted on a rotatably positioned shaft in operative frictioncontact with the flowing mass, a more uniform and easier selection ofindividual switch functions is made possible, as compared with the useof an intermediate hydraulic linkage for actuating the particularlyswitching functions for the valve means. The retarding action of theflowable mass may also be utilized to achieve a preactive delaycondition in a convenient way prior to the active condition of controlof the lever with respect to the valve means in question. Such laminatedswitch may be termed a flowing mass switch or hydraulic delay member.

Understandably, in order to protect the roof from unwanted cave in, itis advisable to advance immediately adjacent prop frame units, or atleast immediately adjacent frames of successive units, one after theother in time, rather than simultaneously, in order to avoid having toolarge a temporarily exposed roof area without any support.

If a hydraulic delay member or flowing mass switch of the aforementionedtype is used as timer device according to the invention, the advancementto zero position from the terminal position for initiating thepre-active and thereafter the active condition may take placeautomatically with suitable locking means preventing a repeat cycle. Ifa spring drive is used, the spring when run down may be recocked, e.g.by turning the lever in the same way as the sweep hand of FIG. 1 isturned to do this. The lever is thus brought back to its initialposition, and the timer device is ready for renewed actuation uponrelease of the locking means therefor.

All in all, the technical means for achieving the timer device controlof the present invention for automatic sequence cycle performance of thevarious advancement steps are well known, and with little effort theartisan can arrange particular constructions to achieve the objects ofthe present invention. This may be undertaken at a relatively slightexpenditure since the timing mechanisms intended need not be precise andaccurate but only roughly so, keeping in mind that the individualoperator may supplement the automatic advancement with correctiveactuations by manual control without danger once the over-all automaticadvancement in the manner of the invention has taken place. While it isconventional to use electric, hydraulic and pneumatic control systemsfor achieving switching performances, even by remote control, accordingto the invention such control systems, even remote control systems, maybe used in a particular manner whereby only one or a few operators areneeded to start the automatic advancement cycle. This is especially truewhere a number of prop frame units are interconnected for successive orsimultaneous actuation and/or where portable transmitters are used by afew operators to advance a given prop frame unit or a group of propframe units interconnected for simultaneous movement, merely upon theparticular operators setting a predetermined frequency on a portabletransmitter attuned to the receiving frequency of a wireless receiverutilized to start the automatic advancement cycle of one or more propframe units.

A particular advantage of the present invention is in utilizing remotecontrol means which avoid the use of any wires which might be damagedduring normal mining operations, thus reducing expenses which might beotherwise necessary. The large number of control lines previouslyrequired to attain automatic advancement of prop frame units is avoidedand in fact the manufacturing costs for attaining the automatic cyclecontrol amount to about /2 to of the costs needed heretofore.

The individual steps for retracting, advancing and extending of the propframes are carried out in short intervals and if for some reason One ofthe steps does not take place properly during the interval assigned forits execution, the next step will occur, and in all instances aretracted frame will in the next subsequent step again be extended bythe timer device control to ensure proper support of the mine roof. Tothis extent there is greater dependability in utilizing the instantconstruction combination than was obtainable with the knownarrangements, such as those in which a particular frame could only beextended into engagement with the mine roof after such frame hadcompleted its full advancing step in the desired direction of advance.

It cannot be over-stressed that the wireless receiver contemplatedherein as well as the timer device and/ or servomotor which may be usedconsume practically no power. The comparatively slight amount of energynecessary for operating the receiver, timer device, servo-motor, etc.,can be readily obtained from a simple electric battery for long periodsof time before recharging of the battery is necessary. Considering thatthe timing mechanism utilized does not need much power for controllingthe pulses or other mechanical or electrical responses which it mustprovide in order to set the working of the particular valve means, thesame will also be able to utilize the power source of the receiver. Thetimer device actually will only control a servo-control, e.g., aservo-motor and linkages, or some similar interposed device which actsin turn to control the flow of hydraulic or pneumatic fluid through thevalve means to accomplish the advancing steps.

In particular, the timer device, wireless receiver, servocontrol, e.g.,servo-motor, and the like, are preferably independent structural unitswhich can be combined in the foriri of the control block, such as thatshown in FIGS. 4 and 5, in the preferred embodiment together with amanual control for the valve means so that versatility in operations maybe attained as well as individual replacement of any of the parts whichwear out or become defective for any reason. By providing the variouscoacting elements in a single device, i.e., a control block, suchcontrol block may be positioned as a compact member on a given propframe whereby to control the advancement of that frame unit or the nextadjacent frame unit, or for that matter a group of frame unitssimultaneously, in the even such frame units are cooperativelyinterconnected to accomplish this result, as the artisan willappreciate.

In view of the various advantages attainable by the versatile use of theinstant combination of elements, in mining operations there will be lessdanger to the miner than can be said for present day prop frame controldevices whether mechanical, automatic and/ or remote.

An important problem which occurs in mining operations utilizing remotecontrol wireless transmitters and receivers relates to decline inefiiciency in transmitting pulses or signals because of the large amountof iron in the form of structural elements in the mineway being worked.Under such conditions, even where a portable wireless transmitter isused, a certain amount of the transmission energy is screened off andaccordingly a given group or groups of prop frame units may not beinfluenced by the transmission energy through the corresponding wirelessreceivers situated therewith. To avoid this possibility and to ensurethat all of the prop frame units intended to be controlled do executethe advancement desired, it is possible in accordance with the presentinvention, as the artisan will appreciate, to lay an antenna along theextent of the mine face and connect with it the individual receiverswhich are far distant from the transmitter so that only the section ofthe antenna nearest to the particular transmitter station and withinrange need be controlled by the transmitter through its attendantsignals. This antenna serves to extend the range of the portablewireless transmitter since it need only influence the portion of theantenna nearest to it, whereas the antenna will carry over thecomparatively long strip of the mineway the transmission energy so thatthe particular receiver intended to be actuated will be in fact soactuated. Of course, the transmission energy can also be stored directlyin a conductor at various points along the mineway by attachment tolines which may be disposed therealong for this purpose.

In relatively complicated mining operations, the individual prop frameunits can be controlled to achieve the step by step advance by theutilization of a cable means, such as that of FIGS. 2 and 3. Preferably,means are provided to ensure that the controlled cycle of a prior timerdevice, in accordance with the present invention, must be completebefore the next successive controlled cycle can be initiated to advancethe next successive prop frame unit. Suitable time control devicesand/or devices which release locking means upon the prior timer devicereaching its end position, analogous to the arrangement shown in FIGS. 1and 2, for instance, may be used to ensure that a given prop unit is notadvanced prior to the desired time and to ensure an orderly sequence ofadvancement in a predetermined manner. Coupled with the foregoing may bedelay action or delay period conditions between the end of onecontrolled cycle for one prop unit and the start of the next controlledcycle for the next successive prop unit, whereby to ensure the safety ofthe miners who may be in the vicinity of the prop units being advanced.

Where an arrangement such as that shown in FIG. 3 is utilized, theextent of axial displacement or longitudinal displacement of the cablewill determine whether the respective prop units are being or have beenadvanced in the desired way. Thus, if a particular unit is not advanced,by indicia markings along the control cable the place of blockage of thecable can be readily ascertained and concomitantly the particular propframe unit which has failed to complete the advancement cycle and whichhas thus prevented release of the locking means for initiating theadvancement cycle of the next unit. Such indications will makeimmediately aware to the operating personnel that a given unit has notproperly carried out the step by step advancement operation and may notbe in effective supporting engagement with the mine roof. The defect maybe easily ascertained, despite the fact that poor visibility orcomplicated operations would otherwise render the ascertainment ofdefects in the automatic advancement operation difiicult, especially inareas remote from the point of observation. Obviously, the use of amarked cable for this purpose is simple in construction and operationand extremely inexpensive to provide.

Indeed, the use of marked cables may be of importance where the first,eleventh, twenty-first, etc. prop units are to be simultaneouslyadvanced, and the second, twelfth, twenty-second, etc. are to be nextadvanced, and so on, since, for example, out of a possible 100 propunits being controlled, such units simultaneously by each cable, theeffective operation of a particular unit may be ascertained by the lackof further movement of the control cable caused by the aforesaid lockingmeans so that the number of possibilities is narrowed immediately to 10,and thence by visual inspection or other means to the single unit whichis defective in operation. The particular cable may be rewound after thefull displacement thereof for attaining the control of the advancementof all of the units in question. However, where a particular lockingmeans has not been released and the cable cannot complete its fulldisplacement, a simple procedure is to rewind the cable and merely checkby visual inspection before further advancement. Any simple mechanismcan also be utilized to determine remotely which prop unit is defectivein its advancement so that it is unecessary to rewind the cable to itsstarting position and attempt visual inspection, but of course the useof a cable arrangement such as that in FIGS. 2 and 3 herein will avoidthe extremely complicated return signal devices usually provided inelectrical control devices presently employed in advancing prop units.As aforesaid, a combination of elements has not been employed before toattain a timed cycle control of the six advancement steps enumeratedhereinabove, with the next step being carried out after a given timeinterval regardless of whether the previous advancement step has beencompleted or not, whereupon the delays caused in the past are notencountered, such delays in particular relating to the breakdown of thecycle where a particular step such as a retractor, extension, or motivemeans actuation cannot execute its full amplitude of operation. Inaccordance with the present invention, it is thus now possible to obtainpartial automation of advancement of prop frame units with relativelycheap structural elements arranged in the novel combination disclosedherein. In particular, it will be appreciated that a fundamental changein the structure of the prop frame units is unnecessary and rather thecombination of the invention may be attained even where the prop unitcontains manual switch controls. Expeditiously, the automatic sequencevalve control means, e.g., timer device, etc., of the present inventionmay be provided as an additional compact control device on a preexistingprop frame unit already containing a manual switching control device toaccomplish versatility in operation for advancement automatically andfor controlling minor adjustments manually with a minimum of danger tothe operating personnel.

It will be appreciated that the automatic sequence valve control deviceof the present invention may be utilized on any given type of propsupport mechanism, including one containing a pair of prop framesinterconnected by a piston-cylinder arrangement such as that shown inaforesaid U.S. Patent 3,192,722, as well as the prop frame unitarrangements of the other aforementioned U.S. patents, and even on theprop frame units disclosed in any and all of the prior art cited in theapplications leading to all of the aforementioned patents. The importantfeature is that a pair of prop means is connected for alternateadvancement in a given longitudinal or linear direction and suchadvancement is normally carried out with a motive means having a firstmotive part connected with one prop means and another motive partconnected with a second prop means, especially by way of apiston-cylinder arrangement with the piston connected to one prop meansand cylinder connected to the other prop means. As used herein, the termprop means does not merely signify a pair of props having a base and aroof cap whereby to form a prop frame, but may signify a singleextensible prop, such as one using the hydraulic jack principle,connected to each motive part, so that the one prop will move with thecylinder and the other prop will move with the piston. Also, a pair ofsuch props may be utilized not in the form of the usual prop frame, ofthe type shown in FIG. 2 or 4, but rather with such props beingconnected for common displacement with the piston or the cylinder of themotive device, such as by connection with such piston or cylinderthrough a base means or a roof cap or through direct connection of eachprop separately from the other with the cylinder itself or the pistonitself. Of course, a multiplicity of props may be carried in a frame orthrough an intermediate connection or directly with the cylinder itselfor the piston itself to accomplish the roof support contemplated as wellas the advancement steps in an automatic manner in accordance with theinvention. Indeed, arrangements are known for connecting a plurality ofprop means as intended by the foregoing language for independentrelative movement of one such prop means with respect to the remainingprop means by suitable hydraulic actuation of motive means designed toaccomplish more than two actuations so as to advance more than two propmeans, such as three prop means. Thus, a piston-cylinder arrangement mayinclude a normal cylinder as well as a normal piston in the form of ahollow piston rod within which a further piston rod is disposed suchthat the hollow piston rod forms an internal cylinder for such furtherpiston rod. In this way, by suitable hydraulic or pneumatic fluid flow,first the further piston and a first prop means connected therewith maybe advanced with respect to the remainder of the device, then the normalpiston forming the cylinder for such further piston may be advanced witha second prop means connected therewith, and then the normal cylinderwith a third prop means connected therewith may be advanced, as theartisan will appreciate. Suitable fluid flow conduit arrangements may beutilized to advance any one of the three motive elements and thecorresponding prop means connected therewith without also displacingeither of the other two motive elements with their respective propmeans, or may be utilized to attain movement of any two of the propmeans with respect to the remaining one of the prop means. As will occurto the artisan, the multiple number of individual prop means advanceablewith respect to the remaining prop means is a matter of expediency andin any of these situations the automatic sequence valve control means ofthe present invention may be adapted to program a given cycle ofprearranged ordinal sequence of control of appropriate valve means toattain the desired results.

To attain the advantages of the present invention, a wirelesstransmitter and receiver may be used of the type found in factories,ofiices, etc., by which a roving person is paged. This is carried out bytransmitting a signal or pulse from the transmitter device to a rovingperson in the area who carries a small frequency receiver on him whichemits a buzzing sound or signal when being called. Such small receiversare capable of response over a sufiicient range, are light, relativelycheap, and simple in construction. The sole function of such receiver isto control an electromagnet which actuates the buzzer or other signal. Asimple battery of the dry cell type may be used in the receiver for theactuation and for powering the receiver itself. In connection with thetimer device of the present invention, for example that shown in FIGS. 4and 5, the small electromagnet is used in the same way, upon a signalbeing received by the receiver, whereby to start the mechanism of aclockwork or some other mechanism which initiates the automatic cyclefor achieving control of the advancement steps. Of course, theelectromagnet may actuate a brake to start and stop the timer, eitherthrough the starting and stopping of an electric switch where the timeris electrically operated or to start the release of a coil spring wherethe clockwork or analogous mechanism is spring operated. In the one casethe timer power is via a manually cocked spring and in the other casethe power to drive the electric clock mechanism may be obtained from thesame battery used to operate the receiver and the electric magnet.Timers of the type contemplated herein are very simple, mass-produceditems, such as the clock mechanism in a wind-up alarm clock or a wind-uptimer of short duration (e.g., one to five minutes), or in a simpleelectrically operated kitchen clock. The cost factor of such a mechanismis indeed slight. The simplicity in construction of a timer, receiver,servo-control, or the like, for operating the valve means for theadvancement steps, lends itself to the use of these elements in a verycompact single package, such as a control block, permitting easyreplacement of the parts and ready substitution of one package foranother on a given prop unit. Of course, the preferred embodimentcontemplates the use of wireless remote transmission and receivingmeans, although a mechanical cable actuation, such as that shown in FIG.2 or FIG. 3, is indeed possible for actuating responsive levers and thelike to achieve the initiation of the controlled cycle advance. Once aparticular timer is initiated, by remote control means, cable means,manually, or otherwise, in accordance with the present invention, theindividual six steps will take place in predetermined ordinal sequenceand for predetermined time intervals adjusted to permit a normalcompletion of a particular step before the next step will automaticallytake place. The receivers, of course, should be protected againstfire-damp, although this will not unduly increase the size of thepackage in question, and the timers need not be extremely accurate sincethe main feature is in attaining the steps for the advancement ingeneral, whereupon manual switching adjustments may be utilized tocorrect any incomplete step caused by slight inaccuracies in timeintervals permitted. The relatively primitive means of the entiremechanism for achieving the remote control advancement of the entireprop units, with elements which may be readily replaceable and be ableto fit into a small space, represents an essential advantage over theprior art.

Moreover, the coupling of the individual timer devices, such as in thearrangements of FIGS. 2 and 3, may be achieved by electrical means, asthe artisan may readily appreciate, even simpler in constructionalarrangement than the mechanical means shown. However, it is notabsolutely necessary that more than one prop unit be coupled with othersfor joint advancement. An alternative form of advancement is to connecta number of receivers to the same antenna laid along the mine face sothat the transmitted signal may be received simultaneously at all of thereceivers connected to such antenna to attain the simultaneousadvancement of the respective prop units associated therewith. A moreversatile control, of course, will be achieved by adjusting thefrequencies of the transmitters to the frequencies of the receivers tobe controlled. Hence, a particular transmitter used to control aspecific prop unit or group of prop units may be adjusted to thepredetermined frequency to which the receiver or receivers for suchspecific prop unit or group of prop units has been previously set.

What is claimed is:

1. An advanceable mining prop arrangement with hydraulically actuatablemotive means, motive valve means controlling such motive means, eachprop being hydraulically actuatable to change the effective lengththereof for alternate extension into and retraction from supportingengagement with the mine roof and mine floor upon hydraulic actuation,in combination with automatic sequence valve control means operativelyconnected with said motive valve means, said sequence valve controlmeans being separately positioned at a remote distance from such propunit sufficiently to permit switching of said sequence valve controlmeans without danger to the operator from the resultant changes incondition of said prop unit and the mine roof area being supportedthereby, said control means so combined with timing means as to operatethem in an automatic timed cycle operation.

2. Arrangement according to claim 1 wherein supplemental manual switchmeans are provided in operative association, separately from saidsequence valve control means.

3. An advanceable mining prop arrangement with hydraulically actuatablemotive means, motive valve means controlling such motive means, eachprop being hydraulically actuatable to change the effective lengththereof for alternate extension into and retraction from supportingengagement with the mine roof and mine floor upon hydraulic actuation,in combination with automatic sequence valve control means operativelyconnected with said motive valve means, said control means so combinedwith timing means as to operate them in an automatic timed cycleoperation, said timing means including an automatic timer device whichwhen switched from inactive to active condition passes through a timedcycle to control the actuation in turn of said valve means in therequired sequence.

4. Arrangement according to claim 3 wherein said timer device includes apreactive condition of preset duration upon being switched from saidinactive condition and prior to attaining said active condition as asafety delay period to permit the operator time to leave the immediateprop unit site before the resultant changes in condition of said propunit and the mine roof area being supported thereby occur upon saidtimer device attaining said active condition.

5. Arrangement according to claim 4 wherein said timer device includes acontrol block provided with a dial face having an active portioncontaining valve means switch contacts ordinally positioned thereonoperatively connected with said valve means to control the correspondinghydraulic flow therethrough, and a sweep hand switch contact which uponbeing switched from said inactive condition is movable from a startingposition initially through a preactive portion of said dial forattaining said preactive condition of preset duration and then throughsaid active portion of said dial in contact for predetermined intervalsin time-controlled sequence ordinally with said contacts to actuate saidvalve means, whereupon said sweep hand switch contact reaches a terminalposition of inactive spent condition.

6. Arrangement according to claim 5 wherein releasable locking means areprovided at said starting position to control the switching of saidsweep hand switch contact from inactive to preactive and activeconditions.

7. Arrangement according to claim 6 wherein a plurality of saidadvanceable prop units, each in combination with a respective automatictimer device, is provided in succession in operative adjacency, thecontrol blocks of such timer devices being operatively connected forsuccessive operation via cable means actuatable to control therespective releasable locking means for release in succession to permitthe separate ordinal sequence actuation of the said valve means foradvancing each prop unit respectively in succession.

8. Arrangement according to claim 7 wherein said cable means includes adisplaceable cable which is provided with a lug thereon positioned fortravel along a path into which said releasable locking means aresituated in succession such that upon actuation to displace said cablesaid lug trips said locking means in succession to release therespective sweep hand switch contacts for carrying out the advancing ofeach prop unit respectively in succession.

9. Arrangement according to claim 7 wherein said cable means includeseparate axially displaceable and thrust sub-cables, each sub-cablerespectively operatively interconnecting the control block of the timingdevice of a prior prop unit with that of the next prop unit insuccession, one end of each such sub-cable being operatively situated atthe terminal position of the control block of the timing device of arespective prior prop unit and in the path of the corresponding sweephand switch contact thereof and the other end of such sub-cable beingoperatively connected with the locking means of the control block of thetiming device of the next prop unit in succession for release of suchlocking means upon axial displacement of such sub-cable, such that uponswitching the control block of the timer device of the first prop unitin succession from inactive to active condition for advancing said firstprop unit and in turn upon the sweep hand switch contact thereofreaching the corresponding terminal position, such sweep hand switchcontact will strike said one end of the corresponding sub-cable betweenthe first prop unit and the next prop unit in succession to cause axialdisplacement of such corresponding sub-cable and in turn cause saidother end of such corresponding sub-cable to release the locking meansof the control block of the timer device of the next prop unit insuccession for advancing said next prop unit, and in turn in the sameway each of the subsequent locking means in succession by theappropriate sub-cable for advancing each of the further prop units oneafter the next until the last prop unit in succession has been advancedand the corresponding sweep hand switch contact thereof has reached thecorresponding terminal position.

10. Arrangement according to claim 3 wherein said automatic timer deviceincludes a drive linkage operatively connected with displaceable cammeans, and cam actuatable response means operatively connected with saidvalve means to control the corresponding hydraulic flow therethrough,said drive linkage, upon switching said timing device from inactive toactive position, being energizable to displace said cam means, andwherein said response means includes follower means positioned in thepath of displacement of said cam means for actuation thereby to controlsaid valve means.

11. Arrangement according to claim wherein said drive linkage includesrotatable gear means, said cam means include a rotatable shaft, having aplurality of cams thereon of predetermined disposition, which isoperatively connected with said drive linkage via said gear means forrotation thereby, said follower means being positioned in the path ofsaid cams for appropriate actuation thereby for predetermined intervalsin time controlled sequence in dependence upon the predetermineddisposition of said cams, and said response means includes a servo-motoroperatively connected with said follower means to control said valvemeans in response to the actuation of said follower means by said cams,and wherein brake means are provided for switching said drive linkagefrom inactive to active condition, such that upon being switched toactive condition, said drive means is able to rotate said shaft via saidgear means and actuate said servo-motor via said follower means forpredetermined intervals in time controlled sequence ordinally.

12. Arrangement according to claim 11 wherein remote control means areoperatively connected with said brake means to actuate said brake meansfor switching said drive linkage from inactive to active condition andin turn from active to inactive condition.

13. Arrangement according to claim 12 wherein said remote control meansinclude a pulse signal transmitting wireless device remote from suchmining prop arrangement and a pulse signal receiving wireless deviceoperatively connected with said brake means for actuating said brakemeans in dependence upon the pulses received.

14. An advanceable mining prop arrangement which comprises anadvanceable mining prop unit including first means having at least oneprop and second means apart from said first means and prop andoperatively inter connected with said first means and prop for alternateadvancement therewith via hydraulically actuatable motive means, motivevalve means controlling the actuation of such motive means, said propbeing hydraulically actuatable to change the effective length thereoffor alternate extension into and retraction from supporting engagementwith the mine roof and mine floor upon hydraulic actuation, and propvalve means, in combination with automatic sequence valve control meansoperatively connected with said motive valve means and prop valve meansfor regulating the corresponding hydraulic flow therethrough inpredetermined ordinal sequence and for predetermined intervals in anautomatic cycle operation, said sequence valve control means beingseparately positioned at a remote distance from such prop unitsufficiently to permit switching of said sequence valve control meanswithout danger to the operator from the resultant changes in conditionof said prop unit and the mine roof area being supported thereby.

15. Arrangement according to claim 14 wherein supplemental manual switchmeans are provided in operative association, separately from saidsequence valve control means, with said motive valve means and said propvalve means.

16. Arrangement according to claim 14 wherein said sequence valvecontrol means include an automatic timer device which when switched frominactive to active condition passes through a timed cycle to control theactuation in turn of said valve means in the required sequence.

17. An advanceable mining prop arrangement which comprises anadvanceable prop unit including hydraulically actuatable motive meanshaving a first motive part and a second motive part operativelyinterconnected for back and forth alternate longitudinal displacementwith respect to each other upon corresponding alternate hydraulicactuation, motive valve means controlling such alternate hydraulicactuation, prop means including a first prop connected to said firstmotive part for longitudinal displacement therewith and a second propconnected to said second motive part for longitudinal displacementtherewith, each said prop being hydraulically actuatable independentlyof the other to change the ef fective length thereof for alternateextension into and retraction from supporting engagement with the mineroof and mine floor upon corresponding alternate hydraulic actuation,and first prop valve means for said first prop and second prop valvemeans for said second prop correspondingly controlling such alternatehydraulic actuation, in combination with automatic sequence valvecontrol means operatively connected with said motive valve means, firstprop valve means and second prop valve means to actuate said valve meansfor regulating the corresponding hydraulic flow therethrough inpredetermined ordinal sequence and for predetermined intervals in anautomatic cycle operation, said sequence valve control means beingswitchable from an inactive condition to an active condition wherein,when both said props are extended into engagement with the mine roof,said sequence valve control means in sequence automatically firstlyactuates said first prop valve means for retraction of said first propfrom engagement with the mine roof, secondly actuates said motive valvemeans for longitudinal displacement of said first motive part and saidfirst prop with respect to said second motive part and said second propin a given longitudinal direction of advance, thirdly actuates saidfirst prop valve means for extension of said first prop into engagementwith the mine roof, fourthly actuates said second prop valve means forretraction of said second prop from engagement with the mine roof,fifthly actuates said motive valve means for longitudinal displacementof said second motive part and said second prop with respect to saidfirst motive part and said first prop in said direction of advance, andsixthly actuates said second prop valve means for extension of saidsecond prop into engagement with the mine roof.

18. Arrangement according to claim 17 wherein supplemental manual switchmeans are provided in operamanual actuation of said valve means.

19. Arrangement according to claim 17 wherein said sequence valvecontrol means are separately positioned at a remote distance from saidprop unit suflieient to permit switching of said sequence valve controlmeans without danger to the operator from the resultant changes incondition of said prop unit and the mine roof area being supportedthereby.

20. Arrangement according to claim 17 wherein said sequence valvecontrol means include an automatic timer device which when switched frominactive to active condition passes through a timed cycle to control theactuation in turn of said valve means in the required sequence.

21. Arrangement according to claim 20 wherein said timer device includesa preactive condition of present duration upon being switched from saidinactive condition and prior to attaining said active condition as asafety delay period to permit the operator time to leave the immediateprop unit site before the resultant changes in condition of said propunit and the mine roof area being supported thereby occur upon saidtimer device attaining said active condition.

22. Arrangement according to claim 21 wherein said timer device includesa control block provided with a dial face having an active portioncontaining six valve means switch contacts ordinally positioned thereonoperatively connected with said valve means to control the correspondinghydraulic flow therethrough, and a loaded spring operated sweep handswitch contact which upon being switched from said inactive condition ismovable under the operative force of said spring from a startingposition initially through a preactive portion of said dial forattaining said preactive condition of preset duration and then throughsaid active portion of said dial in contact for predetermined intervalsin time controlled sequence ordinally with the first contact to actuatesaid first prop valve means for retraction of said first prop, with thesecond contact to actuate said motive valve means for displacement ofsaid first motive part and first prop, with the third contact to actuatesaid first prop valve means for extension of said first prop, with thefourth contact to actuate said second prop valve means for retraction ofsaid second prop, with the fifth contact to actuate said motive valvemeans for displacement of said second motive part and said second prop,and with the sixth contact to actuate said second prop valve means forextension of said second prop, whereupon said sweep hand switch contactreaches a terminal position of inactive spent condition.

23. Arrangement according to claim 22 wherein said control block isresettable to the original inactive condition by return movement of saidsweep hand switch contact to reload said spring to said startingposition.

24. Arrangement according to claim 23 wherein releasable locking meansare provided at said starting position to control the switching of saidsweep hand switch contact from inactive to preactive and activeconditions.

25. Arrangement according to claim 24 wherein a plurality of saidadvanceable prop units, each in combination with a respective automatictimer device, is provided in succession in operative adjacency, thecontrol blocks of such timer devices being operatively connected forsuccessive operation via cable means actuatable to control therespective releasable locking means for release in succession to permitthe separate ordinal sequence actuation of the said valve means foradvancing each prop unit respectively in succession.

26. Arrangement according to claim 25 wherein said cable means includesa displaceable cable which is provided with a lug thereon positioned fortravel along a path into which said releasable locking means aresituated in succession such that upon actuation to displace said cablesaid lug trips said locking mean in succession to release the respectivesweep hand switch contacts for carrying out the advancing of each propunit respectively in succession.

27. Arrangement according to claim 25 wherein said cable means includeseparate axially displaceable and thrust sub-cables, each sub-cablerespectively operatively interconnecting the control block of the timingdevice of a prior prop unit with that of the next prop unit insuccession, one end of each such sub-cable being operatively situated atthe terminal position of the control block of the timing device of arespective prior prop unit and in the path of the corresponding sweephand switch contact thereof and the other end of such sub-cable beingoperatively connected with the locking means of the control block of thetiming device of the next prop unit in succession for release of suchlocking means upon axial displacement of such sub-cable, such that uponswitching the control block of the timer device of the first prop unitin succession from inactive to active condition for advancing said firstprop unit and in turn upon the sweep hand switch contact thereofreaching the corresponding terminal position, such sweep hand switchcontact will strike said one end of the corresponding sub-cable betweenthe first prop unit and the next prop unit in succession to cause axialdisplacement of such corresponding sub-cable and in turn cause saidother end of such corresponding sub-cable to release the locking meansof the control block of the timer device of the next prop unit insuccession for advancing said next prop unit, and in turn in the sameway each of the subsequent locking means in succession by theappropriate sub-cable for advancing each of the further prop units oneafter the next until the last prop unit in succession has been advancedand the corresponding sweep hand switch contact thereof has reached thecorresponding terminal position.

28. Arrangement according to claim 20 wherein said automatic timerdevice includes a drive linkage operatively connected with displaceablecam means, and cam actuatable response means operatively connected withsaid valve means to control the corresponding hydraulic flowtherethrough, said drive linkage, upon switching said timing device frominactive to active position, being energizable to displace said cammeans, and wherein said response means includes follower meanspositioned in the path of displacement of said cam means for actuationthereby to control said valve means.

29. Arrangement according to claim 28 wherein said drive linkageincludes rotatable gear means, said cam means include a rotatable shaft,having a plurality of cams thereon of predetermined disposition, whichis operatively connected with said drive linkage via said gear means forrotation thereby, said follower means being positioned in the path ofsaid cams for appropriate actuation thereby for predetermined intervalsin time controlled sequence in dependence upon the predetermineddisposition of said cams, and said response means includes a servo-motoroperatively connected with said follower means to control said valvemeans in response to the actuation of said follower means by said cams,and wherein brake means are provided for switching said drive linkagefrom inactive to active condition, such that upon being switched toactive condition, said drive means is able to rotate said shaft via saidgear means and actuate said servo-motor via said follower means forpredetermined intervals in time controlled sequence ordinally, firstlyto actuate correspondingly said first prop valve means for retraction ofsaid first prop, secondly to actuate correspondingly said motive valvemeans for displacement of said first motive part and first prop, thirdlyto actuate correspondingly said first prop valve means for extension ofsaid first prop, fourthly to actuate correspondingly said second propvalve means for retraction of said second prop, fifthly to actuatecorrespondingly said motive valve means for displacement of said secondmotive part and said second prop, and sixthly to actuate correspondinglysaid second prop valve means for extension of said second prop.

30. Arrangement according to claim 29 wherein remote control means areoperatively connected with said brake means to actuate said brake meansfor switching said drive linkage from inactive to active condition andin turn from active to inactive condition.

31. Arrangement according to claim 30 wherein said remote control meansinclude a pulse signal transmitting wireless device remote from suchmining prop arrangement and a pulse signal receiving wireless deviceoperatively connected with said brake means for actuating said brakemeans in dependence upon the pulses received.

References Cited UNITED STATES PATENTS 3,207,041 9/1965 Phillips 91-13,285,015 11/1966 Carnegie et al 6145.2

EDGAR W. GEOGHEGAN, Primary Examiner.

U.S. Cl. X.R.

UNITED sTATEs PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,434,389 March 25 1969 Hans-Theodor Grisebach It is certified thaterror appears in the above identified patent and that said LettersPatent are hereby corrected as shown below:

In the heading to the printed specification, line 4, after "Lunen,insert Westphalia,. Column 23, line 19, "present" should read presetSigned and sealed this 7th day of April 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer

